A single Quaalude pill in the pocket of a 19-year-old, long-haired kid in 1979.

That illegal possession of a sedative was enough to put William Michael Dillon’s mug shot and fingerprints in the criminal justice system, and, traveling a topsy-turvy road full of law-enforcement potholes, led to a wrongful conviction for a Brevard County murder in 1981.

That pill was enough to disqualify this 2008 DNA exoneree from having “clean hands” that would have paved the way for easier compensation from the Florida Legislature for the 27 years he spent in prison for a murder he did not commit.

Instead, Dillon’s compensation would have to wait four years until 2012, when a claims bill, shepherded through several sessions by pro bono attorney Sandy D’Alemberte, was finally successful and Dillon received $1.3 million.

On December 13, that prior drug charge was wiped forever off his record when the Florida Clemency Board granted Dillon a full pardon.

“It was a big deal to clean the slate as much as I could,” 53-year-old Dillon said afterwards. “It is important in starting my life again. It is important to how much was missing and what they are willing to give back for it.”

Mark Schlakman, immediate past chair of the board of the Innocence Project of Florida, who represented Dillon pro bono in the recent clemency matter, said: “It is virtually impossible to imagine what it would be like to be wrongfully convicted for a serious crime that you didn’t commit, to be incarcerated for more than a quarter of a century, subjected to unfathomable indignities, while the perpetrator remains free, to be wrenched away from your family and friends and a life that might have been, but never was.

“Bill Dillon doesn’t need to imagine. He lived that nightmare, but he had the will to overcome, to first survive and to overcome the gross miscarriage of justice. . . . Bill was a victim of eyewitness misidentification, junk science, self-interested testimony of a jailhouse snitch, perjured witness testimony, and manufactured evidence.”

Dillon thanks “angels in my life” who helped him overcome. Dillon told Gov. Rick Scott and the clemency board: “My life has taken off like a flower blooms in the spring.”

He has love in his life, Ellen Moscovitz, a DNA analyst expert he met while traveling the country speaking about wrongful convictions.

He has a budding music career, with “Black Robes and Lawyers,” the song he wrote on toilet paper in his prison cell, hitting No. 10 on the iTunes chart. Dillon’s musical break came in May 2010, when veteran music producer Jim Tullio happened to glance at his TV and catch “On the Case with Paula Zahn.” The case was about Dillon, and Tullio — a Grammy Award-winning composer, producer, and engineer — reached out to contact Dillon and brought him to his sound studio near Chicago.

Dillon sang the National Anthem at a Tampa Bay Rays baseball game. Now, he is working on his second CD titled, “Things I Gotta Do.”

On his to-do list is continuing to speak out about wrongful convictions. A new member of the board of directors of the Innocence Project of Florida, in Tallahassee, Dillon said, “I am committed to DNA testing. It’s a must.”

Now that his criminal background slate has been wiped totally clean, he said he is ready to move back to Florida from North Carolina, and he is looking for a home in Boca Raton.

“I’m doing great. I have my moments,” Dillon said.

“My moments are memories and little sad points. But I have beautiful support. I’m loving life and traveling and telling people about wrongful convictions and how to overcome.”